Electropneumatic brake



Dec. 20, 1927. 1,653,134 T. H. THOMAS ELECTROPNEUMATIG BRAKE Filed Feb. 25. 1927 6 EMERG:

LAP

RELEASE BHKWWMV ATTORNEY Patented Dec. 20, 1927.

Y UNiTi-:o fsrA'riazsg gihvrlNT 'OFFICE THOMAS H. THOMAS, OE Eiionvvoon,v PENNSYLVANIA, AssIeNoR'fio THE'WESTING- HOUSE AIR BRAKE COMPANY, OE WIIIMERDING, PENNSYLVANIA, A' CORPORATION OF VPENNSYLVANIA.

ELEOTROPNEUMATIO BRAKE.

Application yfiled Februaryv 23,V 1927. ASerial No. 170,073.

This invent-ion relates to electro-pneumatic brakes and has for its principalobJect to provide an electrop.neumaticbrake systemiii which the application and release of the brakes are controlled throug'lia single train wire. v y n p In the accompanying drawing; Fig. 1 is a diagrammaticviewoic an electro-pneumatic brake system embodying my .invention, as appliedr to a locomotive and one car;

and Fig. 2, a view, partly in scctiomot thev electro-pneumatic rbrake equipment'` employed on the locomotive and on each car.

As shown in Fig. 1 of the drawings, the

locomotive and each cai' is provided with a magnet valve device 1i, a magnet valve de-` vice 2, a rectifier 3 interposed in the circuit or' the 'magnet valve device land adapted to permit flow ofcurrent only in'one direction, said magnet valve device` being connectedv in parallel with the single train wire 4. On

the locomotive is provided a battery or other source of power 5, and a brake switch `6. rl`he locomotive and each' cary is equipped ywith .an electro-pneumatic kbrake equipment 7, as shown in Fig. `2, of the drawing, and comprising the ii'iagiiet valve devices 1 and o valve device 22. i

The magnet valve device 1 comprises ak of a valve 12 contained in chamber 13. The

valves 10 aiid'12 are adapted to'be operated in one direction by operation of themagnet 8` and when said magnet is deenergizedthe pressure of spring 14 shifts the valves -in the opposite direction. i

The magnet valve device .2 comprises a magnet 15, and a casing having a chamber 16 containing a double heat valve 17, adapted to be 'operated by said magnet, and a chamber 18, containing a coil spring y19 adapted to engage a collared stem 20, abut-k ting the valve stem;

The magnet valve devices are so 'constructed that a lower vvoltage willy operate the magnet 8 than is required to operate the magnet 15. f The rectifier 3 is disposed in the circuit .of the magnet valve vdevice 1 Land ,is4 adapted to permit the lowof current only in `one a triple valve device 21 and a yselectorV direction, as indicated by the arrow on each rectifier. 'f

The brake switch 6, `located on the locomotive, @may comprise a contact` drum*V adapted to beroperatedby a handleg'the ro-y tation ot. said drum being adapted to eiect thev electrical connections :inv the various ypositions of the brake switch, as shown in the development of said switch.

.The electro-pneumaticbrake' equipment 7 is similar to that disclosed in my prior Patent No. 1,440,421, issued on January 2, 1923,*aiidmay comprise a lquick action triple valve device 21., andy a selector valve portion 22, both of whicliare mounted on a bracket 23, to kwhichthe auxiliary reservoir 24 and brake cylinder 25 are also connected. Mounted on a bracket integral with the selector valve portion yare the ymagnet valve devices 1 and 2. i

-- 'The triple valve device 21 may comprise i the usual casing having. a' piston chamber 26 connected tothe brake pipe y81 and consisy taining a piston 27, and a. valve chamber 28' connected to the auxiliary reservoir24` and containing a main slide valve 29 and an erated by said piston.'

t yThe quickl action portion of `the triple valve devicemay comprise lthe .usual piston '31 contained in chamber32, and adapted to i auxiliary slide valve 30, adapted to be opi operate'tlie brake'pipe vent valve 33l con-y tained kin chamber 34. Also vContained in chamber34`is the usualcheck valve 35.

Theselector valve portionV 22r comprises a casing having a piston chamber 36 connected through passage 37 to chamber'16v of the magneti `valve device 2, andcontaining lal piston 38, and a valve chamber 39 connected through passage 40 to valve chamber 28of the triple valve device,y and containing a slide valve 41,adapted torbe operated by `said'piston A coil, spring 42, contained in piston chamber 36,act`s` on the yface of the piston 38. e Y

vThe singley train wire 4 is continuous throughout thetrain, being connected between cars by a jumper 43. f

The brake switch 6 is separable from the usual automatic brake valve device (not shown) vand is adapted to be operated'independently, while the automatic brake valvepdevice remaiiis in the usualV running position.

eisy

.contact 84, wire 70, contact85, wire 49,

In operation, the fluid pressure brake system is charged in the usual manner, and lluid from thebralre pipe 81 flows to piston chamber 26 of the triple valve device and thence through the feed groove 44 to valve chamber28 and the auxiliary reservoir 24. Fluid from the valve chamber 28`is supplied through passage to the selector valve chamber V32 and from passage 40 through passages and 51 to `valve chambers. 13 and 18 of the magnet valve devices 1 and 2. i In-the combined release and running position of the brake switch, the train wire 4 circuit is` closed through a portion of the battery -5 by way of drum. contact 82, Wire 65, drum 'Contact 83, wire -45 connected to "an intermediate point 62 of the battery,

thence to the negative pole .64 oit the battery, wire` 49, drum contact 66, wire 48, and ground 47. i

The current thus supplied from a portion of the batteryJ 5 flows through the train wire 4 to the magnet 8 through the rectifier 3 and through wires69 to magnet 15,'and thence to the common ground 46. This current is not sullicient to eliectively energize the magnet 15, but the magnet 8 is energized by the current. i

The magnet 15 not being effectively energized,-the double beat valve, 17 is seated in its upper position, as shown in the cra fing, in which position fluid at brake pipe pressure from chamber 18 is permitted to 'flow through passage `37 to the selector piston chamber 86. rlhe pressures on the opposite sides ot the selector piston 38 therefore become equalized and the pressure of spring` 42 holds said piston and the slide valve 41 in. the release position, as shown in the drawing.` The magnet 8 being energized, the `valve 10 is seated and thevalve 12 is unseated, `which permits `fluid atbrake pipe pressure from chamber 13 to flow into chamber 11 and thence through passage 52 and pipe 50 to a reservoir 54. `l3assage52 also leads to the seat ot the selector slide valve 41, but is lapped in the release position of the, slidevalve.

lV ith the selector piston 38 and slide valve 41 in release position, and with the triple valve device 21 in release position, the brake cylinder 25 is connected' to the atmosphere through passages 55, 56, 57, cavity 58 in the triple valve slide valve 29, passage 59, cavity 60 in the selector slide valve 40 and the atmospheric exhaust passage 61.

To effect a service application of the brakes, the brakeswitch 6 ismoved, independently of the usual automatic brake valve ldevice (not shown), to` seri/*ice position, in which the train wire `4 circuit is closed through the whole battery 5 by way ot drum negative pole 64 ofthe battery 5, through the battery to the positive pole 63 of the battery 5, wire 67, contact86, wire 68, contact 87, wire 48 and ground 47. i

It will be noted that current flows through the train wire 4 in the opposite direction trom the flow when the brake switch is in release position, and since the rectifier 3 prevents ilow in this direction, current is only suppliedthrough wire'69 to magnet 15 which becomes energized while the magnet 8 is deenergized.

The magnet 15 being energized, it operates to shift the double beat valve 17 to its lower position, in which communication between chambers 16 and 18 is closed, and chamber' A16, which'is connected through passage 37 to the selector piston chamber 36, is connected to chamber 71 and thence to the atmosphere through the exhaust passage 72. Fluid under pressure is thus vented from the piston chamber 36 and the opposing pressure in the valve chamber 89 then shifts the piston 38 and slide valve 41 downwardly to application position against the pressure oit spring 42.

vWith the selector valvev in application position, communication between the brake cylinder passage v59 and the exhaust passage 61, is cut 0E, and the brake cylinder passage 59 is lapped. The passage 52 is connected to the valve chamber 39 and cavity 73 in the slide valve connects passage 74 to passage 75.

The magnet 8 being deenergized, the pressure oit spring' 14 closes the valve 12 and opens the valve 10, which permits the flow ot fluid under pressure trom `chamber 11,V cenuected to the reservoir k54 and selectorh valve chamber 39, yto chamber 9 and thence through passage. 7 6, past the check valve 77. through passage 75, cavity78 in the selector slide valve, passages 74, 57, 56 and 55 to the brake cylinder 25, thereby applying the brakesY The selector valve chamber 3,9 being connected through passage 40 to the triple valve slide valve chamber 28, the pressure of the fluid in the valve chamber o9 and reservoir isv maintained from the auxiliary reservoir 24' when applying the brakes.

.Y li' it is desired to limit the brake cylinder y pressure to some particular degree, the brake switch 6 is moved to lap` position, when the :desired pressure is attained in the brake i cylinder.

tery to the train wire 4 and thence through Y y.the rectilier 3 and magnet valve device 1 and gemma-z wire 69' and the magnet valve device 2te the ground 46. The lenergization of the magnet is thusv retainedthe same as in service position, and in addition the magnety between service and lap positions, as de` scribed, the brake cylinder pressure may be increased in steps up to the degree at which the brake cylinder pressure becomes equal to i the pressure of the duid inthe brake pipe.

To release the brakes, the brake switch 6y ismoved to. the combined running, and release position in which the-magnet 8 becomes energized and the magnet 15 becomes deenergized, as herein 'before described. Energization oi the magnet. v8 operates'to prevent flow of fluid tothe brake cylinder, while deenergiZat-ion of the magnet `15 permits vthe balancing of fluidv pressures on the Opposite sides of the selector` piston, with a consequent shiftingofsaid piston-and slide valve 41 to release position, by the pressureofthe spring'42. In release position of the selector slide valve 41, passage 59 from the brake cylinder 25 connected thro-ugh cavity 60 in 4the slide valve tothe exhaust passage 61, thereby permitting the venting oit fluid :from the brake cylinder 25, with a consequent release oi the brakes. i v n Il?k lt is desired to limit `the yventingof brake cylinder pressure,thefbrake switch G is moved to `lap position after the desired decrease in -brake cylinder pressure is obtained, in which position further change inv brake cylinder pressure lis prevented. yBy alternately moving lthe brake switch between release and lap positionsyas described,

a graduated release of the brakes is effected.

To eliect an emergency application ofthe brakes, the brake switch 6 is movedy to emergency position, in which position the circuit in the train wire 4 is opened, so that both of themagnetsB and 15 are .deener gized.

y Since the magnet=15 is deenergized, the! selector valve piston 38 will be maintained in release position, the supply of fluid undery pressure to the pistonchamberfti being maintained from chamber` 18 past the open double beat valve 17. n

The magnet 8 being deenergized, the valve 12 will be closed andthe valve 10 opened, so that fluid under pressure isl supplied lfrom 4the normally charged reservoir 54 to open the brake pipe vent valve 33 and conneet chamber 34 to chamber 93, which is connected through passage 55 to the brake cylinder 25, Thel fluid under lpressure in vthe brakefpipe `thenylifts the check yvalve '35 and iows through the chambers 34 and 93 to the brakevcylindenthereby electing aflocal reduction in the brake pipe pres--k sure, inthe usual manner.A

Said reduction in Lbrakev pipe `'pressure causesV the triple valve y'piston 27 to shift theslide valves 29` and 30to emergency position, in whichv Huid yunderl presure in theauxiliary reservoir 24 and valve cham` ber 28 is permitted to liow thronghport 80 in the main slidel valve and into passage' and thence through passages 56 and. 55 to the brake cylinderv 25, vand thus apply the brakes in emergency. i

When an emergencyapplication ofthe brakes is effected inthe above described manner, the continuedy flow of fluidunder pressure yin the brake pipe 81 will be cut y off at the locomotive by, movement ofthe automatic brake valve device (not shown) to emergency or lap position.. f

f It the train current shonldfailyan emergene-y application of thefbrakes will kbe electedin f the samefmanner Vasfwhen the brake switch is moved tok emergency position.

Ita, car equipped 'with the above kdescribed yapparatus is'placed in a trainnot provided with electric control, the r`magnets 8y and 15 'will both be deenergized. The

'MAO

double beat vvalve 17y will therefore be, in its 'upper position, in which it,y will permit anequalization of pressures on the selector valve piston, sokthat said piston will remain in its'release position.' The valve 12 controlled by magnet 15 willbeclosed, so that brake .pipe fluid cannot flowinto chamber 11, so vthat with the valve 10, 0pen,ithe chamber 11 and reservoir 54 kwill be connected to` the quick action vpiston.31 and thence 'tor the bra-ke cylinder passage 56to the atmosphere in the usual manner; Sincey there is no tluid in the vreservoir54-nnder the above conditions,y there fwill be no action of the electric portion, andthe equipment will only act pneumatically, as controlled by the automatic brake valve device on lthe locomotive.`

llO

It it is `desired to Aoperate the brakes pneumaticallylat the same timeas electrically, a plug in a passage91 is removed and placed in the threaded opening 92in the passage 40, so as to close'the auxiliary reservoir passage 40 and open thebrake pipe passage 91.

i With thisV arrangement, it will be i seen that uponl the combined operation of the pneumatic brake valve andelectricrbrake switch, fluid' under pressure will he taken from the brake pipebyway of .passage 91, instead of .from the auxiliary reservoir through passage 40, to eti'ect an application of thevbrakes electrically. Thisinsures that the auxiliary reservoir pressure Will be higher than` the brake pipe pressure, which is reduced at the brake valve device as Well as through operation of the electric equipment in service position, so that the triple valve deviceswill operate to move to service position and applythe brakes.

As hereinbefore explained, When an electricnservice `application of the brakes is eiected,the liuid for applying the brakes is taken from the auxiliary Y reservoir through passage 40. The auxiliary reservoir pressure therefore tends to be reduced, but is substantially maintained by. iloW from the brake pipe S1 through the 'eed groove 44 around the piston 27, on account of the usual automatic brake valve device on the locomotive remaining in running position, in which the brakepipe pressure is maintained. i w

0n account of the brake pipe and auxiliary reservoir pressures being maintained during electric operation, the ability to obtain a brake application Whenever and as often as desired is assured, and furthermore, asupply of 'fluid isalways insured for securingr an emergency application of the brakes.v e Y l* f Having non' described my invention, what I claim as nen7 anddesire to secure by I ietters `Patent,is:-

i l. In an electrically controlled brake, the combination with a single train ivire,ofl tivo electrically controlled devices connected to said Wire for controlling the brakes, one effectively energizable by current Vat a strengthivhich will not ei'fectively energize the other device, and means for preventing flow otcurrent through one ot tliedevices in one direction.

.2, In an electrically controlled brake, the combination With a'single train Wire, of tivo electrically controlled devices connected to said Wire .for controlling the brakes, one device being ed'ectively energized by current at a strength which Will not effectively energize the other device, and means for preventing iloiv of currentthrough the first mentioned device in one direction. y

3. In an electrically controlled brake, the combination with aV single train Wire, ot means for impressing a current on said Wire at one currentstrengtli in one direction at `one time and a current at a different current strength in the opposite direction at another time, and electrically controlled means connected to said train .vire and lcontrolled ,according to the direction and strength of current flowing through said Wire. Y

et. In an electrically controlled brake, the combination withv a single train Wire, ot means for supplying currentl to said Wire in one direction at one current strength at one time, .at another current strength at any time, and for supplying current to said Wire in the reverse rdirection at another time, and electrically controlled means operated according to the strength and direction of current through said Wire for controlling the brakes.

VY5. In an electrically controlled brake, the combination With a single train Wire, of two electrically controlled devices connected to said Wirefor controlling the brakes, means in circuit `With. one device for permitting i'loW of current through said device only'in one direction and eltectively energized by current at a strength insutlicient to elfectively energize the other device.

6. In anelectrically controlled brake, the combination with a single train Wire, of two electrically controlled devices connected to said ivire for controlling the brakes, means in circuit withV one device for permitting flow of current through said device only in `one direction and eliect-ively energized by current at a strength insuiiicientv to effectively energize the other device, and means for supplying currentat the'diilerent strengths to said train Wire.

7. yIn an electrically controlled brake, the

combination with a single train Wire, of a i brake sWi-tchdevice having a release position in .which i current at one current strength and flowing in one direction is supplied to saidwtrain vvire, and a brake application position, in which `current is supplied to said `train Wire at a different current strength, and lioiving in the reverse direction, and electrically controlled devices connected to said train Wire and controlled according to the direction and strength of current in said Wire for controlling the application and release of the brakes.

8. In an electrically controlled brake, the combination with a single train Wire, of a brake switch device having a. release position in which current at one current strength and flowing in one direction is supplied to said train Wire, a brake application position, in which current is supplied to said train Wire at a different current strength and iloW-` ing in thel reverse direction, and a lap posi-- tion, in which the direction of currentlow is the same as inl release position,and the strength of current is the same as that in service position, and means operatedaccording to variations in the 'direction of iioW and strength of current for controlling the brakes.

Q In an electrically controlled brake, the

`combinationivith a single train Wire, of tivo electrically controlled devices connected to said train ivirevforcontrolling the brakes and means whereby current supplied to saidv train Wireivill energize one device to effect the release of the brakes, energize the other device to edect an application ofthe brakes,

1,653,134 Y y* B and energize both devices to hold the brake applied or released. Y

10. In an electrically controlled brake, the combination with a single train Wire, of two electrically controlled devices connected to said train Wire for lcontrolling the brakes and means whereby current supplied to said train Wire Will energize one device to e'ect the release 'of the brakes, energize the other* device to effect an application of the brakes, and energize both devices to hold the brakes applied or released, the brakes being also In testimony whereof I have hereunto set my hand. n THOMAS H. THOMAS.

applied upony deenergization of both devices.k 

